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Gravitation energy harvesting of climbed down objects is a promise to harvest unused potential energy from a host building or structure. Similarly, a dynamically dropper mechanism is proved to be a simple and effective electric energy generator, with many practical implementations in power, civil, and mechanical engineering. This research analyzes the prospect of using a mechanism which tends to be...
This paper presents a simulation study of a polluted insulator under a direct lightning impulse current. The pollution condition was considered and divided into two cases which are partial and full pollution. Under those conditions, the electromagnetic profiles of the insulator were evaluated. In the study, six points of measurement recognised as the weak points of the insulator were introduced to...
Lightning events are one of the factors that affect performance of a solar power system either by direct or indirect strikes. When lightning strikes directly to a panel, it can affect function and life cycle of the panel. Therefore, considering the electrical performance characteristics such as open-circuit voltage, short-circuit current, and maximum power of the solar panels under high voltage conditions...
This study analyzed and compared the lightning related casualties in Malaysia and United States. United States as a developed country is reported with 0.3 deaths per million per year after 1970 comparing to lesser-developed areas such as Malaysia with an annual lightning fatality rate of 6 deaths per million. The comparison and analysis were made based on the rural-urban setting and the six types...
When a tower is struck by lightning, an induced voltage can generate in conducting objects within its vicinity. This phenomenon is due to the interaction between the electromagnetic field of the lightning with the object. The magnetic field is part of this field. Previous studies have shown that the magnetic field is affected by ground reflection coefficient factors that are usually taken as constants...
A direct lightning strike to a tall structure can impart high impact damage to electrical equipment that may be installed within and around the structure. This is due to the behaviour of the lightning return stroke current which generates a lightning electromagnetic field (LEMF) and consequently creates an induced voltage (LIV) on the electrical equipment. The lightning return stroke current along...
A solar PV system was modelled and the effect of lightning striking different parts of a solar PV system was studied and the results discussed appropriately. Lightning strikes of different wave shapes and different magnitudes were considered. The purpose of this research is to observe the transient current and voltage that appears in a solar PV system when struck by lightning. The results show that...
One of the factors that cause power outages on distribution lines is being struck by lightning. Cloud to ground lightning often affects overhead distribution lines and can occur with negative or positive polarities. It can affect the performance of insulators and cause power line failure. Furthermore, outdoor polymer insulators are exposed to extreme weathering and pollution, which can cause chemical...
This study examined the risk of lightning-related deaths and injuries in Malaysia between January of 2008 to July 2015. The majority of lightning-related injuries and fatalities occurred during the months of April and May. Most lightning related casualties reported in the statistics since 2008 occurred in the states of Melaka and Selangor in the western coastal belt. The majority of victims, were...
This paper reviews a study of the inclination angle of an insulator due to mechanical forces imposed by overhead conductors. The angle theoretically shortens the effective leakage path and flashover distance of the insulator, thus change the electrical performance of the insulator. To take it into consideration, this study had focused on experimental works to investigate effect of insulator inclination...
This paper presents a study on the AC breakdown voltages of Palm Oil (PO) and Coconut Oil (CO) with presence of TiO2. The type of PO used in this study is Refined, Bleached and Deodorized Palm Oil (RBDPO). TiO2 was added into RBDPO and CO at volume concentration of nanoparticles ranging from 0.001% to 0.05% In total, 50 measurements of AC breakdown voltages were recorded and analyzed by Weibull and...
Dissolved Gas Analysis (DGA) is one of the common approaches that can be used to detect incipient faults in transformers. According to IEEE C57/104-2008 and IEC 60599 standards, there are many DGA techniques that can be used to interpret the type of faults. In this paper, an alternative method to diagnose faults in transformers based on Rough Set (RS) and Fuzzy Logic (FL) is proposed. The rules for...
Liquid insulation plays an important role for the lifespan of the oil-filled transformer. Liquid insulators not only insulate the live parts of the transformer, but also act as cooling agent for better heat agglomeration when the transformer being energized. Petroleum-based mineral oil has become dominant transformer oil for more than a century for its excellent dielectric properties. Considering...
Photovoltaic (PV) system has non-linear powervoltage (P-V) characteristic with single maximum power point (MPP) in uniform condition. The P-V curve would be more complicated during partially shaded (PS) conditions (PSCs) when multi-peak powers exist. The point with the highest value of power among the multi-peak powers is called global maximum power point (GMPP). In this paper, a novel hybrid method...
Energization current is a fundamental consideration in designing of distribution substation earth grid. Arbitrary choice of energization current in earth grid design process may lead to technical and economic implications resulting in underestimated or overestimated designs. In this paper, a distribution substation earth grid was designed using SESCAD and executed in MALT module of CDEGS. The energization...
The increasing interests on the Palm Oil (PO) and Coconut Oil (CO) as a potential alternative for dielectric insulating fluid in transformers encourage a number of researches on different aspects of these oils. Among the common areas under study is the lightning breakdown voltage. In this paper, the lightning breakdown voltage of PO and CO is examined. The type of PO used in this study is Refined,...
Site dependent parameters such as soil resistivity, maximum grid current, fault duration, shock duration, surface layer material resistivity, and grid geometry have substantial impact on the design and performance of an earth grid. The grid geometry, i.e. the area occupied by the grid system, conductor spacing and the depth of burial of earth grid specifically have much impact on the mesh, step, touch...
One of the important parameter for insulating fluid is the dielectric properties. With the introduction of vegetable oil as possible alternative fluid for transformers application, it is essential to ensure this type of oil could meet the dielectric properties requirement. In this paper, a study is carried out to investigate the dielectric properties of Palm Oil (PO) and Coconut Oil (CO). The type...
Being in one of the highest region of lightning is truly a big challenge to the utilities operating transmission and distribution lines where lightning related cause of tripping has become the major concern every year. Tenaga Nasional Berhad (TNB) in Malaysia is one of those utilities facing the huge challenge in ensuring the line performance is maintained so as to conform to the National Grid requirement...
Down-conductor is part of critical component in the external Lightning Protection System (LPS) as to divert the lightning current from the air termination to the earth termination system of protected structure. In this paper, numerical analysis approach incorporating the effect of copper conductor bending angle under current transient and voltage is utilized. Various angles of copper conductor will...
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